The present invention relates to a housing for a typewriter or similar office machine of the type having a housing cover located in an upper housing portion between a platen and a keyboard. The housing cover is movable from a closed position to an open position in which functional elements, which are movable along the platen, are exposed.
Typewriters and similar machines are known in which an upper part of the housing terminates as a removable cover. Below this cover there are components, such as a printing mechanism movable along the platen, and exchangeable functional elements such as a daisywheel and a ribbon cartridge. After removal of the housing cover, free access is gained to this printing mechanism without having to disassemble the entire housing from the machine. It is possible to arrange the housing cover on the machine so that it can be completely removed from the machine and set aside. Alternatively, such a cover has been fastened to the housing by way of hinge elements and can be folded upwardly. When the housing cover is closed, it is advantageous, and in the folded open position of the housing cover, it is necessary, to arrest the cover in its respective positions by means of locking elements.
More expensive typewriters and word processors are additionally provided with a line display device which displays at least a few of the most recently put in characters before they are printed out on the record carrier or typing paper. The operator is able to check his or her character input on this display device and make corrections, if necessary, before printout.
German Offenlegungsschrift (published unexamined application) 2,742,992, which is a counterpart to U.S. Pat. No. 4,212,077, discloses a typical example of a machine having the display device disposed in the front cover constituting the transition region near the keyboard and between the upper housing member and the lower housing member. For a skilled operator typing by touch with his or her gaze directed onto the platen to observe progress and format of the printed text, this arrangement makes it necessary for his or her eyes to constantly move back and forth between the typed line at a higher level and the display device at a lower level. This back and forth movement of the operator's eyes is necessitated by the need, on the one hand, to check the character input while it still can be corrected and, on the other hand, to monitor the typing progress and, thus, his or her adherence to the intended format.
The solution disclosed in German Offenlegungsschrift (published unexamined application) 2,939,184 overcomes this drawback. In that device, a very small display device is disposed in the immediate vicinity of the typed line, that is, in the region of the type carrier, so that the operator can read the typed line and immediately thereafter follow the not yet typed characters displayed on the display device. However, given its necessarily small size, the manufacture and accommodation of such a display device involves significant technical problems. Additionally, it is difficult for the operator to read the characters, which in such an arrangement can be displayed only in a very small size, owing to the poor reproduction quality of the display as compared to the printed image. Another drawback is that only a few of the most recently put in characters can be displayed at one time. Also, given that the display device is designed to be displaced along the printed line, the display device must be very short. Thus, such a display device can only serve as a monitoring and correction aid for typographical errors noted immediately after input.